作　　者： ; ; ; ;

机构地区： 肇庆学院生命科学学院

出　　处： 《热带亚热带植物学报》 2012年第2期149-155,共7页

摘　　要： 研究了连续6昼夜人工热胁迫(40℃/35℃)对苋菜(Amaranthus tricolor)两个栽培品种绿叶苋和花红苋叶片的组织结构、苋菜红素和热稳定蛋白含量及光合特性的影响。结果表明:6昼夜高温胁迫后,花红苋叶中苋菜红素大量积累,第6天时的含量是绿叶苋的1.81倍。苋菜红素在花红苋叶片下表皮、维管束细胞和上表皮中积累,但绿叶苋则不明显。花红苋栅栏组织结构正常,但绿叶苋出现部分断裂,叶绿体受损较为严重。花红苋叶片的叶绿素和类胡萝卜素含量降幅较绿叶苋低,热稳定蛋白含量轻微上升,其光补偿点和饱和光强比绿叶苋明显滞后。高温胁迫6 d后,绿叶苋的光合速率、胞间CO2浓度和气孔导度等光合参数均显著低于花红苋(P<0.01)。可见,高温下苋菜红素在组织或细胞中的积累与花红苋的耐热性密切相关,较好地维持了花红苋叶片相对稳定的光合性能。 The leaf structure,amaranthin and heat stable protein contents,as well as photosynthetic characteristics were studied in leaves of two cultivars of Amaranthus tricolor L.,such as ＇Red flower＇ and ＇Green leaf＇,under the artificial thermal stress of 40℃/35℃（day/night） for 6 days.The results showed that the amaranthin accumulated greatly in leaves of ＇Red flower＇,its content was 1.81 times of that in ＇Green leaf＇ under high temperature for 6 days.Under light microscope,amaranthin distributed in lower and upper epidermis,vascular bundle of ＇Red flower＇,but did not appear in ＇Green leaf＇.The palisade tissue structure remained normal in ＇Red flower＇,but it partially discontinued and chloroplasts damaged seriously in ＇Green leaf＇ after 6 days under high temperature stress.Compared with ＇Green leaf＇,the chlorophyll and carotenoids contents in ＇Red flower＇ decreased slightly,the content of heat stable proteins slightly rise,and its light compensation points and saturated light intensity obviously delay.After high temperature stress,the photosynthetic parameters,such as net photosynthesis rate（Pn）,intercellular CO2 concentration（Ci） and stomatal conductance（Gs） in ＇Green leaf＇ were significantly lower than those in ＇Red flower＇（P0.01）.It suggested that the accumulation of amaranthin was closely correlated with the thermostability of ＇Red flower＇ under high temperature,which was benefited to maintained a stable photosynthetic performance.

关 键 词： 苋菜叶 高温胁迫 苋菜红素 光合特性 叶片结构

领　　域： [农业科学]